CHAPTER 9. INSTRUCTION SET

XCH A, @HL

Function: A (HL)

Exchanges the contents of the A register and the contents of the data memory addressed by the contents of register pair HL.

Application example: Exchange the data of data memory addresses 20H to 2FH and the data of addresses 30H to 3FH.

MOV HL, #30H

 

LOOP: XCH

A, @HL

; A (3×)

MOV

H, #2

 

XCH

A, @HL

; A (2×)

MOV

H, #3

 

XCH

A, @HL

; A (3×)

INCS

L

; L L + 1

BR

LOOP

 

XCH A, mem

Function: A (mem); mem = D7 to D0 ; 00H to 3FH

Exchanges the contents of the A register and the data memory contents addressed by 8-bit immediate data mem.

XCH XA, mem

Function: A (mem), X (mem + 1); mem = D7 to D0 : 00H to 3EH

Exchanges the contents of the A register and the data memory contents addressed by 8-bit immediate data mem and exchanges the contents of the X register and the contents of the next memory address.

mem can specify even addresses.

XCH A, reg1

Function: A reg1

Exchanges the contents of the A register and the contents of register reg1 (X, H, L).

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NEC PD75P402, PD75402A user manual Loop XCH, Mov Xch, 161